6.18-stable review patch. If anyone has any objections, please let me know.
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From: Ma Ke make24@iscas.ac.cn
commit 970e1e41805f0bd49dc234330a9390f4708d097d upstream.
driver_find_device() calls get_device() to increment the reference count once a matching device is found. device_release_driver() releases the driver, but it does not decrease the reference count that was incremented by driver_find_device(). At the end of the loop, there is no put_device() to balance the reference count. To avoid reference count leakage, add put_device() to decrease the reference count.
Found by code review.
Cc: stable@vger.kernel.org Fixes: bfc653aa89cb ("perf: arm_cspmu: Separate Arm and vendor module") Signed-off-by: Ma Ke make24@iscas.ac.cn Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/perf/arm_cspmu/arm_cspmu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/perf/arm_cspmu/arm_cspmu.c +++ b/drivers/perf/arm_cspmu/arm_cspmu.c @@ -1365,8 +1365,10 @@ void arm_cspmu_impl_unregister(const str
/* Unbind the driver from all matching backend devices. */ while ((dev = driver_find_device(&arm_cspmu_driver.driver, NULL, - match, arm_cspmu_match_device))) + match, arm_cspmu_match_device))) { device_release_driver(dev); + put_device(dev); + }
mutex_lock(&arm_cspmu_lock);